Effects of Lower Body Plyometric Training on Serum CPK and Creatinine Levels in Collegiate Female Volleyball Players: An Experimental Study

Intervention adapted from James & Robert (2015). Experimental group completed progressive lower-body plyometrics twice weekly (Monday/Wednesday) over eight weeks with warm-up and cool-down. Exercises included squat jump; jump to box (30 cm); tuck jump; split squat jump; lateral hurdle jump (50 cm); zigzag jump; single-leg tuck jump; and depth jump (80 cm). Control group continued routine volleyball activities and did not perform low/medium/high-intensity plyometrics. Primary biomarker (serum CPK) assessed via CK-NAC optimized IFCC method; serum creatinine by modified Jaffe's method. Two-way ANOVA with Bonferroni post hoc used. Findings: CPK increased from day 2, peaked day 4, stabilized to week 2, then declined toward baseline by week 8; creatinine remained stable.